US4376045A - Liquid treatment apparatus - Google Patents

Liquid treatment apparatus Download PDF

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Publication number
US4376045A
US4376045A US06/262,108 US26210881A US4376045A US 4376045 A US4376045 A US 4376045A US 26210881 A US26210881 A US 26210881A US 4376045 A US4376045 A US 4376045A
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United States
Prior art keywords
tube
liquid
nozzles
tank
solids
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
US06/262,108
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English (en)
Inventor
David A. Siskind
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Ecodyne Corp
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Ecodyne Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Ecodyne Corp filed Critical Ecodyne Corp
Assigned to ECODYNE CORPORATION reassignment ECODYNE CORPORATION ASSIGNMENT OF ASSIGNORS INTEREST. Assignors: SISKIND DAVID A.
Priority to US06/262,108 priority Critical patent/US4376045A/en
Priority to CA000399255A priority patent/CA1167391A/en
Priority to AU81985/82A priority patent/AU547338B2/en
Priority to GB8209399A priority patent/GB2098080B/en
Priority to MX192351A priority patent/MX159186A/es
Priority to ES512033A priority patent/ES8307668A1/es
Priority to IT48369/82A priority patent/IT1147962B/it
Publication of US4376045A publication Critical patent/US4376045A/en
Application granted granted Critical
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D21/00—Separation of suspended solid particles from liquids by sedimentation
    • B01D21/30—Control equipment
    • B01D21/34—Controlling the feed distribution; Controlling the liquid level ; Control of process parameters
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D21/00—Separation of suspended solid particles from liquids by sedimentation
    • B01D21/02—Settling tanks with single outlets for the separated liquid
    • B01D21/08—Settling tanks with single outlets for the separated liquid provided with flocculating compartments
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D21/00—Separation of suspended solid particles from liquids by sedimentation
    • B01D21/24—Feed or discharge mechanisms for settling tanks
    • B01D21/2488—Feed or discharge mechanisms for settling tanks bringing about a partial recirculation of the liquid, e.g. for introducing chemical aids
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D21/00—Separation of suspended solid particles from liquids by sedimentation
    • B01D21/30—Control equipment

Definitions

  • This invention relates to liquid treating apparatus and more particularly to apparatus that employs sedimentation to remove dissolved and undissolved solids from water.
  • Such equipment may have a solids settling zone, a solids mixing and recirculation zone and a solids uptake zone.
  • the bottom of the uptake zone communicates with the settling zone and the upper end of the uptake zone communicates with the mixing and recirculation zone.
  • the lower portion of the mixing and recirculation zone communicates with the settling zone.
  • Solids from the settling zone and treatment chemicals are mixed with incoming untreated liquid in the uptake zone. This is accomplished by flowing the incoming liquid and treatment chemicals into the uptake zone through nozzles which cause a turbulent updraft in a tube that draws settled solids upwardly into the uptake zone.
  • the quantity of solids recirculating in such apparatus should be maintained in an optimum range to insure ample solids to achieve coagulation and clarification, while preventing solids from being discharged with the treated liquid.
  • the quantity of solids being recirculated will also change.
  • Prior arrangements used to adjust the recirculation of solids to compensate for changes in liquid flow were not automatic and hence depended on an operator to detect the flow change and to make the proper equipment adjustments. Also, prior manual flow adjustment arrangements were not always effective at the lowest flow rates.
  • Another object is to automatically control the volume of solids recirculating in liquid sedimentation apparatus.
  • Another object is to eliminate the need for plant operating personnel to detect flow changes and to manually adjust the equipment to compensate for such changes.
  • Another object is to provide means for controlling recirculation of solids in sedimentation apparatus that maintains maximum pumping energy input.
  • Another object is to provide adequate mixing of recirculated solids in the uptake zone of a liquid clarifier at low flow rates.
  • Another object is to prevent excessive solids recirculation or turbulence from developing at the highest flow rates.
  • Another object is to provide simple, durable, automatic means for controlling the solids recirculation rate in water sedimentation apparatus that is relatively low cost, easily maintained and which does not possess defects found in similar prior art apparatus.
  • FIG. 1 is a cross sectional side view of a schematic representation of liquid treatment apparatus embodying the invention.
  • FIG. 2 is an enlarged cross sectional view taken along the line 2--2 in FIG. 1.
  • FIG. 3 is an enlarged cross sectional view corresponding to FIG. 2 but showing another embodiment of the invention.
  • FIG. 4 is a cross sectional side view of the embodiment of FIG. 3.
  • the drawing shows apparatus 1 that treats and clarifies liquids by sedimentation.
  • This kind of equipment is used for softening water by the cold lime-soda ash process, and for the clarification of waters containing suspended solids, color, and organic impurities by coagulation with alum or ferric sulfate or other coagulants. Coagulation and softening can be carried out simultaneously.
  • the coagulants or precipitates formed within the apparatus have an enormous surface area upon which the dissolved or colloidally dispersed impurities are absorbed.
  • the suspended impurities are surrounded by the gelatinous precipitates and themselves become part of the precipitate, which settles to the bottom of the apparatus.
  • calcium hydroxide is added to the water to precipitate the calcium bicarbonate as calcium carbonate and the magnesium salts as magnesium hydroxide.
  • Sodium carbonate is added to the water to react with the calcium chloride and calcium sulfate originally present in the water as well as that formed by the reaction of calcium hydroxide with magnesium chloride and sulfate. The reaction of sodium carbonate with these salts forms calcium carbonate.
  • the calcium and magnesium salts originally present in the water are removed as the slightly soluble compounds, calcium carbonate and magnesium hydroxide, precipitate out.
  • a coagulant such as alum, sodium aluminate, or ferric sulfate can be employed in the treatment to assist in the separation of the turbidity, precipitates, and other solids formed from the water.
  • Apparatus 1 includes a cylindrical open-topped tank 2 having a bottom 3 which slopes downwardly to a conical sump 4 where settled solids are collected.
  • An overflow weir 5 at the upper end of tank 2 collects treated water for discharge through an outlet line 6 and determines the upper surface level of the water in tank 2.
  • a rotatable rake 7 adjacent bottom 3 pushes settled solids toward sump 4.
  • Rake 7 is connected to vertical shaft 8 which is rotated by a motor and gear box assembly 9 in conventional manner.
  • Shaft 8 extends through the center of tank 2.
  • Sludge thickeners 10 in sump 4 are also turned by shaft 8 and settled solids are removed from the sump for disposal through discharge line 11.
  • a cylindrical, open-ended, vertical updraft tube 12 is coaxial with shaft 8.
  • Tube 12 may have a predetermined constant diameter for most of its length and an enlarged lower end portion 13.
  • the bottom edge 14 of enlarged portion 13 terminates above but adjacent to rake 7.
  • the upper edge 15 of tube 12 terminates below the upper level of the water in tank 2.
  • a plurality of upwardly directed nozzles 16 and 17 are uniformly spaced around the inside of tube 12 intermediate its ends.
  • a manifold 18 for incoming untreated water surrounds tube 12 and an inlet 19 of each nozzle 16 and 17 communicates with the inside of the manifold.
  • An inlet line 20 connects manifold 18 to a pressurized source of untreated water.
  • the pressurized water exiting from nozzles 16 and 17 flows rapidly up and out of upper end 15 of tube 12; this draws settled solids from the bottom of tank 2 into lower end 14 and forces such settled solids up through tube 12 and out its upper end 15 with the incoming untreated water.
  • the inside surface of tube 12 defines a solids uptake zone 21 for transporting previously settled solids into the upper part of tank 2.
  • Water treating chemicals may be mixed with the incoming untreated water and fed in through line 20, or they may be added separately through one or more chemical inlet lines, such as 22.
  • a cylindrical baffle 23 surrounds and is coaxial with tube 12.
  • the upper end 24 of baffle 23 extends above the upper level of the water in tank 2, and the lower end 25 of baffle 23 terminates above the lower edge 14 of tube 12.
  • the inside surface of baffle 23 defines a generally annular solids mixing and recirculation zone 26 above and around tube 12 within the confines of the baffle.
  • the turbulent liquid flow in zone 26 mixes the treatment chemicals and the incoming untreated water with the previously settled solids from the bottom of tank 2.
  • the previously settled solids will adhere to newly formed precipitates and to solids that enter with the untreated water and thereby increase the overall solids settling rate of apparatus 1 when the previously settled solids are present in the proper ratio.
  • the outer surface of baffle 23 and the inside surface of tank 2 define a solids settling or sedimentation zone 27 that surrounds baffle 23 and tube 12.
  • Apparatus 1 includes pressure sensitive means 30 for automatically regulating the quantity of previously settled solids drawn upwardly into tube 12.
  • automatic regulation is achieved by placing a spring actuated poppet valve 31 in the water inlet passage 32 of each valve 17 inside of manifold 18.
  • the strength of the springs in valves 31 is selected so that the valves will be closed at the lowest inlet flow volume in the predetermined flow range for apparatus 1, and so that the suction at the bottom of tube 12 is generally constant from about one-quarter to maximum flow rate.
  • Nozzles 16 are always open. There should be an even number greater than five of nozzles 16 and 17, and valves 31 are placed in every other nozzle.
  • the outlet ends 33 of nozzles 16 and 17 may have the same size.
  • valves 31 begin to open in proportion to the volume of liquid flowing into manifold 18. This causes the size of the liquid inlet passage 32 in nozzles 17 to vary in proportion to the volume of liquid flow, while at the same time dissipating some of the pressure of the incoming liquid against the springs in valves 31. This automatically regulates the flow through and pressure in tube 12 to ensure that enough solids will be drawn up into tube 12 at the lowest flow volumes, while preventing excessive flow velocities of liquid exiting from tube 12 at the highest flow volumes from causing turbulence that interferes with sedimentation in zone 27.
  • FIGS. 3 and 4 show another embodiment of the invention that is identical to that of FIGS. 1 and 2, except as shown and described hereafter.
  • Automatic regulation is achieved by placing a weighted valve closure member 35 in the upwardly directed outlet end 36 of each nozzle 17 inside of tube 12.
  • Members 35 seat in valve passages 37 and are held in alignment with their seats by wings 38.
  • Nozzles 16 are always open, but the weight of members 35 is selected so that they will be seated to close passages 37 at the lowest inlet flow volume for the predetermined flow range for apparatus 1.
  • outlet ends 33 of nozzles 16 and 17 need not be identical, but the size of the ends 33 of nozzles 16 is predetermined so that flow through tube 12 produces adequate solids recirculation at the lowest inlet flow volume in the predetermined flow range of Apparatus 1.
  • members 35 begin to lift off the seats in passages 37 in proportion to the volume of liquid flowing into manifold 18. This causes the size of the water inlet or valve passages 37 to vary in proportion to water flow volume, and at the same time dissipates some of the pressure of the incoming water against the pull of gravity on weighted member 35 to maintain a generally constant suction at the bottom or inlet end 14 of tube 12.
  • This automatic regulation has the same benefits described above with reference to FIGS. 1 and 2.
  • Apparatus 1 may include conventional clarifier components and structural members, such as supports for the baffle, tube and weir, handrails, walkways and the like. However, such items have not been shown or described because their details do not form a part of the present invention.
  • a liquid clarifier or sedimentation apparatus may be operated over a widely varying range of inlet flow rates. This is accomplished because incoming liquid flows through only half of the recirculation nozzles 16 and 17 at the lowest flow rates. These nozzles 16 are sized to produce enough pumping action in tube 12 to recirculate sufficient settled solids to ensure proper liquid treatment at the lowest flow volumes. As incoming flow increases, pressure sensitive means in the form of valves 31 or weighted closure members 35 respond to the increased pressure in nozzles 17 to open liquid flow passages. This accommodates increased liquid flow volume and permits a proportional increase in the quantity of solids recirculated, but prevents excessive flow velocities exiting from tube 12 to interfere with sedimentation. Plant operating personnel need not detect or respond to changes in inlet flow volume.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Separation Of Suspended Particles By Flocculating Agents (AREA)
  • Centrifugal Separators (AREA)
US06/262,108 1981-05-11 1981-05-11 Liquid treatment apparatus Expired - Fee Related US4376045A (en)

Priority Applications (7)

Application Number Priority Date Filing Date Title
US06/262,108 US4376045A (en) 1981-05-11 1981-05-11 Liquid treatment apparatus
CA000399255A CA1167391A (en) 1981-05-11 1982-03-24 Liquid treatment apparatus
AU81985/82A AU547338B2 (en) 1981-05-11 1982-03-26 Liquid treatment apparatus
GB8209399A GB2098080B (en) 1981-05-11 1982-03-31 Liquid treatment apparatus with variable liquid flow rates
MX192351A MX159186A (es) 1981-05-11 1982-04-21 Aparato mejorado para el tratamiento de aguas residuales por precipitacion de solidos e impurezas organicas en suspension
ES512033A ES8307668A1 (es) 1981-05-11 1982-05-10 "aparato de tratamiento de liquidos, particularmente de sedimentacion y clarificacion".
IT48369/82A IT1147962B (it) 1981-05-11 1982-05-10 Apparecchiatura per il trattamento di liquidi,in particolare per la separazione di solidi

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US06/262,108 US4376045A (en) 1981-05-11 1981-05-11 Liquid treatment apparatus

Publications (1)

Publication Number Publication Date
US4376045A true US4376045A (en) 1983-03-08

Family

ID=22996186

Family Applications (1)

Application Number Title Priority Date Filing Date
US06/262,108 Expired - Fee Related US4376045A (en) 1981-05-11 1981-05-11 Liquid treatment apparatus

Country Status (7)

Country Link
US (1) US4376045A (es)
AU (1) AU547338B2 (es)
CA (1) CA1167391A (es)
ES (1) ES8307668A1 (es)
GB (1) GB2098080B (es)
IT (1) IT1147962B (es)
MX (1) MX159186A (es)

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4576720A (en) * 1984-05-18 1986-03-18 Mandt Mikkel G Subcyclonic jet recirculation grit removal system
US4647372A (en) * 1984-07-31 1987-03-03 Alsthom-Atlantique Sludge belt apparatus for clarifying liquid charged with solid matter
US4956080A (en) * 1987-08-03 1990-09-11 Microlift Systems, Incorporated High pressure oxygen-saturated water treatment apparatus
US4981366A (en) * 1989-02-27 1991-01-01 Suburbia Systems, Inc. Method and apparatus for mixing liquid contents in a vessel
US5021153A (en) * 1989-11-20 1991-06-04 G-H Systems, Inc. Combined apparatus for removing grit and grease from sewage
US5384049A (en) * 1991-09-03 1995-01-24 Murphy; D. Thomas Wastewater treatment process
US5534143A (en) * 1990-09-18 1996-07-09 Louisiana State University Board Of Supervisors, A Governing Body Of Louisiana State University Agricultural And Mechanical College Microbubble generator for the transfer of oxygen to microbial inocula, and microbubble generator immobilized cell reactor
US5601704A (en) * 1994-04-11 1997-02-11 The Graver Company Automatic feedback control system for a water treatment apparatus
US6276537B1 (en) 1998-12-09 2001-08-21 John K. Esler Enhanced flocculation and energy dissipation feedwell assembly for water and wastewater treatment clarifiers
US6736275B2 (en) 2002-01-22 2004-05-18 United States Filter Corporation Flocculating energy dissipating well arrangement (FEDWA)
US20070187342A1 (en) * 2006-02-10 2007-08-16 Abney Cort Backwash tank and process
US20110100931A1 (en) * 2009-11-05 2011-05-05 Westech Engineering, Inc. Method of optimizing feed concentration in a sedimentation vessel
US20110132846A1 (en) * 2009-12-04 2011-06-09 Flsmidth A/S Feedwell dilution system for thickeners in oil sands

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AU728638B2 (en) * 1996-09-12 2001-01-11 Robert Hume Pannell A thickener or clarifier
ES2242488B1 (es) * 2003-02-28 2007-08-16 Ecologicwash S.L Sistema integrado para el tratamiento y reciclado de aguas residuales sanitarias e industriales.
GB201003668D0 (en) * 2010-03-05 2010-04-21 Airmix Technologies Ltd An improved mixing apparatus

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2381589A (en) * 1940-09-24 1945-08-07 Stanley A Hayes System and apparatus for distributing liquid solutions
US2987007A (en) * 1957-07-30 1961-06-06 Wallace & Tiernan Inc Injector
US3397788A (en) * 1965-10-21 1968-08-20 Union Tank Car Co Water treating apparatus
US3441045A (en) * 1966-12-02 1969-04-29 Boeing Co Variable orifice nozzle mixing ejector
US3951806A (en) * 1974-10-18 1976-04-20 Ecodyne Corporation Clarifier apparatus
US4272369A (en) * 1979-12-13 1981-06-09 Sydlo Inc. Liquid treatment apparatus
US4303517A (en) * 1979-01-15 1981-12-01 Sydlo Inc. Liquid treatment apparatus

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2381589A (en) * 1940-09-24 1945-08-07 Stanley A Hayes System and apparatus for distributing liquid solutions
US2987007A (en) * 1957-07-30 1961-06-06 Wallace & Tiernan Inc Injector
US3397788A (en) * 1965-10-21 1968-08-20 Union Tank Car Co Water treating apparatus
US3441045A (en) * 1966-12-02 1969-04-29 Boeing Co Variable orifice nozzle mixing ejector
US3951806A (en) * 1974-10-18 1976-04-20 Ecodyne Corporation Clarifier apparatus
US4303517A (en) * 1979-01-15 1981-12-01 Sydlo Inc. Liquid treatment apparatus
US4272369A (en) * 1979-12-13 1981-06-09 Sydlo Inc. Liquid treatment apparatus

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4576720A (en) * 1984-05-18 1986-03-18 Mandt Mikkel G Subcyclonic jet recirculation grit removal system
US4647372A (en) * 1984-07-31 1987-03-03 Alsthom-Atlantique Sludge belt apparatus for clarifying liquid charged with solid matter
US4956080A (en) * 1987-08-03 1990-09-11 Microlift Systems, Incorporated High pressure oxygen-saturated water treatment apparatus
US4981366A (en) * 1989-02-27 1991-01-01 Suburbia Systems, Inc. Method and apparatus for mixing liquid contents in a vessel
WO1992007652A1 (en) * 1989-02-27 1992-05-14 Innovative Material Systems, Inc. Method and apparatus for mixing liquid contents in a vessel
US5021153A (en) * 1989-11-20 1991-06-04 G-H Systems, Inc. Combined apparatus for removing grit and grease from sewage
US5534143A (en) * 1990-09-18 1996-07-09 Louisiana State University Board Of Supervisors, A Governing Body Of Louisiana State University Agricultural And Mechanical College Microbubble generator for the transfer of oxygen to microbial inocula, and microbubble generator immobilized cell reactor
US5384049A (en) * 1991-09-03 1995-01-24 Murphy; D. Thomas Wastewater treatment process
US5601704A (en) * 1994-04-11 1997-02-11 The Graver Company Automatic feedback control system for a water treatment apparatus
US6276537B1 (en) 1998-12-09 2001-08-21 John K. Esler Enhanced flocculation and energy dissipation feedwell assembly for water and wastewater treatment clarifiers
US6736275B2 (en) 2002-01-22 2004-05-18 United States Filter Corporation Flocculating energy dissipating well arrangement (FEDWA)
US20070187342A1 (en) * 2006-02-10 2007-08-16 Abney Cort Backwash tank and process
US20110100931A1 (en) * 2009-11-05 2011-05-05 Westech Engineering, Inc. Method of optimizing feed concentration in a sedimentation vessel
US8123955B2 (en) * 2009-11-05 2012-02-28 WesTech Engineering Inc. Method of optimizing feed concentration in a sedimentation vessel
US20110132846A1 (en) * 2009-12-04 2011-06-09 Flsmidth A/S Feedwell dilution system for thickeners in oil sands
US7988865B2 (en) * 2009-12-04 2011-08-02 Flsmidth A/S Feedwell dilution system for thickeners in oil sands

Also Published As

Publication number Publication date
GB2098080B (en) 1985-05-01
ES512033A0 (es) 1983-08-01
AU547338B2 (en) 1985-10-17
IT1147962B (it) 1986-11-26
MX159186A (es) 1989-04-28
AU8198582A (en) 1982-11-18
GB2098080A (en) 1982-11-17
IT8248369A0 (it) 1982-05-10
ES8307668A1 (es) 1983-08-01
CA1167391A (en) 1984-05-15

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Owner name: ECODYNE CORPORATION, A CORP. OF DE.

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Effective date: 19810422

Owner name: ECODYNE CORPORATION

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Effective date: 19870308